How severe is CVE-2021-22923?

CVE-2021-22923 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-22923 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-22923?

CVE-2021-22923 primarily affects Haxx Curl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-22923?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-22923 published?

CVE-2021-22923 was published on 2021-08-05 and last updated on 2026-06-17.

CVE-2021-22923

CVE-2021-22923 is a medium-severity vulnerability in Haxx Curl with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-319.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 2.6
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-319
Affected product: Haxx Curl
Published: 2021-08-05
Last modified: 2026-06-17

Description

When curl is instructed to get content using the metalink feature, and a user name and password are used to download the metalink XML file, those same credentials are then subsequently passed on to each of the servers from which curl will download or try to download the contents from. Often contrary to the user's expectations and intentions and without telling the user it happened.

Frequently asked questions

What is CVE-2021-22923?: When curl is instructed to get content using the metalink feature, and a user name and password are used to download the metalink XML file, those same credentials are then subsequently passed on to each of the servers from which curl will download or try to download the contents from. Often contrary to the user's expectations and intentions and without telling the user it happened.
How severe is CVE-2021-22923?: CVE-2021-22923 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-22923 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-22923?: CVE-2021-22923 primarily affects Haxx Curl. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-22923?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-22923 published?: CVE-2021-22923 was published on 2021-08-05 and last updated on 2026-06-17.

References

Affected products (17)

cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:clustered_data_ontap:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql_server:*:*:*:*:*:*:*:*
cpe:2.3:a:siemens:sinec_infrastructure_network_services:*:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
cpe:2.3:a:splunk:universal_forwarder:*:*:*:*:*:*:*:*
cpe:2.3:a:splunk:universal_forwarder:9.1.0:*:*:*:*:*:*:*

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